Trailer hitch



Patented Oct. 3, 1950 OFFICE TRAILER HITCH Vactor G. Garnett, Pasadena Calif. Application October 2, 1948, Serial No. 52,510

4 Claims. (Cl. 280-33.05)

This invention relates to a device for attaching a trailer to a tow car and has forits principal object the provision of means whereby, when the trailer is following in a straight line with the tow car, it will be relatively closely coupled therewith and so constructed that, when the tow car turns either to the right or left, the device will automatically increase the distance between the tow car and trailer to prevent any interference between the sidewardly turning bodies of the two vehicles.

The advantages of the improved hitch reside in the fact that a greater load carrying capacity can be obtained from the tow car and trailer without increasing the total length of tow car and trailer. This advantage becomes valuable due to the various State laws, which limit the length of a combined tow car and trailer so that any intervening space between the two results in load carrying loss.

Other objects and advantages reside in the detail construction of the invention, which is designed for simplicity, economy, and efiiciency.

These will become more apparent from the following description.

In the following detailed description of the invention, reference is had to the accompanying drawing which forms a part hereof. Like numerals refer to like parts in all views of the drawing and throughout the description.

In the drawing:

Fig. 1 is a plan view of the improved trailer hitch as it would appear upon a trailer following a tow car in the straight ahead position;

Fig. 2 is a similar view illustrating the action of the device when the tow car makes a left turn; and

Fig. 3 is a longitudinal section taken on the line 3-3, Fig. 1.

In the drawing, a tow car is indicated by the numeral In with its rear wheels at H and a trailer is indicated at l2. The tow car In is provided with the usual longitudinally extending chassis members i 3 and the trailer is provided with transversally extending chassis members Id. The trailer I2 is provided with a medially positioned tongue tube l 5 fixedly secured at the middle of the frame members i4 and open at both of its extremities.

A cylindrical tongue bar I 6 extends throughout the length of the tongue tube l5 and is prevented from moving rearwardly therein by means of a front collar ll. A nut I3 is threaded on the rearward extremity of the tongue bar it to prevent it from moving forwardly in the tongue tube l5. It is however, free to rotate in this tube. The forward extremity of the tongue bar [6 terminates in a. bifurcated clevis IS.

A track member, preferably consisting of two inwardly facing, uniformly spaced channel members 20 extends transversally across the rear of the tow car Ill. The two channel members 2a are uniformly separated from each other at the top by means of a spacer plate 2| and arein open spaced apart relation at the bottom. The channel members 20 are supported in any desired manner as by welding them to the rearward extremities of the chassis members I 3. I

A draw bar 22 extends forwardly beneath the channel members 20 to a pivot member 23 on the extremity of a swinging link 24. The link 24 is mounted on the lower extremity of a link shaft 25 which is journalled in a vertical bearing member 26 secured to one of the chassis members l3. The rearward extremity of the draw bar 22 is supported from a roller 21 vertically positioned between the channels 20. A roller shaft 28 ex-- tends downwardly through the draw bar 22 to support the latter.

The rearward extremity of the draw bar 22 is fitted between the furcations of the clevis I9 and is hingedly secured therein by means ofa draw bar pin 29. The draw bar pin is positioned horizontally so as to allow relative vertical movement between the tow car and trailer and so as to prevent relative horizontal movement between the draw bar 22 and the tongue bar I6. Lateral tilting movement between the tow car and the trailer is accommodated by rotation of the tongue bar IS in the tongue tube I5.

It can be readily seen that, if the tow car turns toward the left, the channel members 20 are swung toward the right over the draw bar 22 causing the roller 27 to move rearwardly. This rearward movement is accommodated by the link 24 which also swings rearwardly as shown in Fig. 2. This rearward movement of the link and the roller is imparted to the draw bar 22 to increase the coupled distance between the two vehicles.

The same procedure accommodates a right turn in which event the channels 20 will swing to the left about the roller 21. The entire draw bar load is transmitted through the roller to the channels 20.

While a specific form of the improvement has been described and illustrated herein, it is to be understood that the same may be varied, within the scope of the appended claims, without departing from the spirit of the invention.

Having thus described the invention, what is claimed and desired secured by Letters Patent is:

l. A device for coupling a trailer to a tow car comprising: a track member extending across the rearward extremity of said tow car transversely thereof and inclined rearwardly towards opposite ends; a vertically positioned roller movably supported by said track member movable towards the ends thereof from a normal position midway the length thereof; a draw bar supported from said roller below said track member; a. swinging link pivoted atits one extremity to the front end of said draw bar; means for hingedly mounting the other extremity of said transversely spaced relation to the longitudinal center of the tow car to maintain the forward ex tremity of said draw bar substantiallyontthe. center line of said tow car; and means for attaching a trailer to the rearward extremity of said draw bar having pivotal connection with the draw bar.

2. A device for coupling a trailer to a tow car comprising: a transversally extending track member extending across the rearward extremity of said tow car and having portions extending diagonally at a rearward incline from the transverse center of the tow car towards opposite sides thereof; a vertically positioned roller supported by said track member and movable along the track member-from a normal position at the center of the'track member towards the ends thereof; a drawbar supported at its rear end from said roller below said track member; a swinginglink extending transversely of thetow car and pivoted at its one extremity to the front end of said draw bar; means for .hingedly mounting the other extremity of .said linkon said tow car about a ver-' tical'axis to maintain the forward extremity of said draw barsubstantially on the center line of said towcar; a horizontal draw bar pin mounted at the rearward extremity of said draw bar; a

tongue bar hingedly mounted at its front end on said pin for tilting in a vertical plane; a-tongue .tube fixedly mounted longitudinally on said-trailer at the forward extremity of the center thereof, said tongue bar extending throughout the length .of said tongue tube and longitudinally thereof;

and means for preventing longitudinal movement of said tongue bar in saiditcngue tube.

link on said tow car in 3. A device for coupling a trailer to a tow car" comprising: a hollow transversely extending track member fixed adjacent the rear end of said tow car and formed with a longitudinally extending slot in its under portion; a draw bar; a guide roller in said track member, a shaft projecting upwardly from said draw bar adjacent the rear end thereof and through the slot of said track member and rotatably carrying said roller; a pivot'ba'r-with one end vertically pivoted to a side of saidtowca'r for swinging movement longitudinally of the tow car, and with the other end ver- 'tically pivoted to said draw bar adjacent the forwardend thereof at a point adjacent the longitudinal center line of said tow car; and a tongue consisting of companion members slidably and rotatably engaged with each other and being one fixed to the trailer'longitudinally thereof and the other pivoted at its front end to the rear end of said draw bar.

AHA device for coupling aetrailer .to .a tow car comprising: a transversely extendingtrack member'fixed adjacent the rear end of said tow car; a drawbar a guide member attached to saidl'draw baradjacentlthe rear end thereof and engaging said track member; a longitudinally movable {pivot bar with one end vertically pivoted toa si'de vof said towlcar, and with the other end vertically lpivotedfto said draw bar adjacent the "forward end thereof at'a point adjacentthe longitudinal center'line of said tow car; aihitch member with the forward end thereof'horizontally pivoted to the rearend of said drawbarg'a" longitudinally extending sleeve fixed to said trailer telescopically and rotatably engaging said hitch member; and means to. maintain said hitch member in telescopic and rotatable engagement with said, sleeve.

"VACTOR G. GARNETT.

REFERENCES CITED The followingrreferences are of recordin the @fileof this patent:

UNITED STATES PATENTS Number Name Date 2,001,408 Burton 'May' 14,1935 I 2,328,387 Meats- Aug. 31,1943 

